Apparatus for grinding the worn ends of valve tappets and the like



H. R. BILLETER July 14, 1953 APPARATUS FOR GRINDING THE WORN ENDS OF VALVE TAPPETS AND THE LIKE Filed Feb 17, 1950 66 @9126 Jy mZy Patented July 14, 1953 UNITE-D sTArEs PATENT APPARATUS For: GRINDING T-HE WORN ENDS 0F VALVE TAPPETS AND THE LIKE Henry Robert Billeter, Highland Park, 111., as- Signor to 'Ain'mco Tools, me, North Ghicag' o,

Ill., a corporation of Illinois ApplicationFebruary 17, 1950, Seria lNo, 144,648

'5 Claims. (Cl. 51- 241) invention relates to grinding apparatus and it has to do particularly with apparatus forgrinding the worn ends of valvetappet's commonly employed in internal combustion engines of the "auto,- motive type, particularly valve tappe't's of the type employed in side valve engines. My invention also has utility in other instances where similar problems are tobe met, for example, in the grindin the cam' follower shank bya forced threaded fit wherein the pitch of the threads on the valve tappet stems varies with respect to the pitch of the internal threads provided in the cam follower stem. Thus, repetitious removal of the valve tappet invariably causes wearing of the threads on either the valve tappet or the cam follower stem with a consequent loss of the desired bindin action When the ta'ppets areresto'red to their position in the engine. 7

To overcome the foregoing limitations, attempts have been made to process the worn ends of the valve tappets while the same remain 'in position in the automotive engine, but without success. One common expedient currently resortedftois the removal of the valve and its stem from the valve guide overlying the valve tappet and the passage through the guide of a rotary grinding tool, the lower end of which has thereon an abrasive material. Rotation of the grinding tool within the valve guide when in contact with the upper end of the valve tappet is purported to effect the desired valve tappet processing operation. However, due to the fact that the axis of rotation of the abrasive grinding surface coincides with the axis of the valve tappet, the outer circumferential regions of the abrasive move at a higher speed and impart a greater abracling action than the inner regions thereof so that the extrem central region ofthe surface to be ground receives practically no abrasive action whatsoever. Furthermore by such a grinding operation very little of the expended abrasive or of the removed metal can be expelled from the end of the tappet and the net result is that when the grinding operation is terminated a central nob or hump is'left on the end of the valve tappet.

The prin'cipal'o'bject of my invention is to provi'de a novel grinding means adaptedfor grindlng worn valve tapp'ets without removing them from their assembled position in the engine,

Another object is to provide a portable grindfing device or the foregoing character adapted to operate upon the ends of "worn valve tappets to effect a uniform grinding operation over the entii'ejsurface thereof, and which receives its support from a stationary part or the vehicle engine and derives its proper alignment with the ndb f the valve 'tappet from the aXis of the Valve guide employed in connection with the usual i valve instrumentalities of the internal combustion'engine.

stillfanother object is provide a grinding device of the foregoing nature which "may Conveniently deriveits ower from a small ortable electric drill of the typeinvariably forming a parcel of the-ordinary garage oifmech'a'n'ics equipment. v v

A further object is to provide a grinding device of this character wh'ioh is extremely compact'and which, as 'eonsequenee, may be manufactured in very small dimensions, thereby enabling "the same m be conveniently applied tolall or the valve tappe'ts ordinarily en euntered in an ih'teifial combust on, engine. including the end tapp'ets the valve chamber which are less accessible than the'mediai valve taiibets,

7 Additional objects are to provide "a grinding eo- 'pa'ratus which comprised of a minimum number of moving parts, and which therefore is iinlikely"to get out or order; one which is rugged and durable; one in Which'the moving parts thereof are enciosedwithin a casing :andw'hich are thereforeprotected against contamination "by foreign material, yet which may readily be removed therefrom "for the purpose of inspect on or repair one in which the actual'abrading element perse'is 'reQdiIyteIHCS'V'akfle for the p'l'i-i'pose "or replacement; the which may be manufactured at arelatively low cost; and one which otherwise is well adapted to perform the services required of it. a

I Other objects and advantages will appear as this description progresses and by reference to the drawing wherein- Fig. '1 is a fragmentary sectional view taken transversely through a portion of an internal combustion engine in the vicinity of the valvechamber thereof and showingmy improved valve tappet grinding device applied to a valve tappet. for

grinding purposes;

Fig; 2 is an enlarged sectional vievv taken substant'ially along the line 2-2 of Fig. 1; and

Fig. 3 is a sectional view taken substantially along the line 33 of Fig. 2.

Referring now to the drawing, and in particular to Fig. 1, a fragmentary portion of an internal combustion engine is shown partly in section and includes the usual cylinder block I from which the cylinder head has been removed. A valve opening or port I2 which may be an exhaust port leading to the exhaust passage I4 is adapted to be controlled in the usual manner under the influence of a valve I6 (shown in dotted lines) and including a cylindrical valve head I8 and stem portion 20 which is adapted to be guided in the vertical bore 22 of a valve guide 24 secured in a bore 26 provided in the block I0 and extending between the exhaust passage I4 and the valve chamber 28. The cylinder 30 in which a piston 32 is slidably disposed is separated from the valve chamber 28 by means of a wall 34 which merges into a hub portion 36 having disposed therein the usual tappet aligning sleeve 38 which in turn has slidably disposed therein a cam follower 40, the lower end of which rests upon one of the cams 42 carried by the cam shaft 44 contained within the engine crank case 46.

The cam follower 40 includes a stem portion 48 having a threaded bore 50' formed in the upper end thereof and which is adapted to threadedly receive therein the split threaded shank portion 52 of a valve tappet 54 having formed thereon the usual polygonal adjusting element 56, above .which there is disposed the operative thrust surface 58 which is designed for engagement with the extreme lower end of the valve stem 20.

The valve stem, when the valve I6 is in assembled position in the block I0, carries at its lower end a cup-washer 60 which is situated upon the usual half-moon or other similar retainer 62. A spring 64 surrounds the valve stem 20 and guide 24 and bears at its upper end against a stationary surface provided on the block I0 and at its lower end it is received within the cup-washer 60 to maintain the proper tension upon the valve tending to normally close the valve port I2.

The improved grinding apparatus comprising the present invention is comprised of a tappet grinding assembly designated in its entirety at I2 (Fig. 1) and of a cooperating detachable drive shaft or spindle I4, the latter being preferably formed of hardened steel and of such diameter that it fits snugly within the bore'22 provided in the valve guide 24 for rotary and sliding movement thereon. It will be understood, of course, that when thedrive shaft or spindle I4 is passed through the guide 24 for cooperation with the assembly 12, it is necessary to remove the valve I6 and its associated parts including the spring 64, cup-washer 60 and half-moon retainer 62 from the block I0.

The tappet grinding assembly is shown in detail in Figs. 2 and 3 and includes a gear carrier 'in the form of a cylindrical housing I6 having a top wall I8, a bottom wall 80 and a cylindrical side wall 82. The bottom wall 80 is provided with a cylindrical opening 84 therein in which there is inserted a cup-shaped member 86 having an annular retaining flange 88 for retaining the member 86 within the opening 84. The lower end of the cup-shaped member 86 projects outwardly of the housing I6 and is provided with a smooth polished bearin surface 90 designed for engagement with the upper surface 92 of an abrasive disc or wheel 94 in a manner and for a purpose that will be set forth presently.

The cup-shaped member 86 forms a bearing for the lower end or hub portion 96 of a driving gear 98 which is rotatably disposed within the housing 16. The upper end or hub portion I00 of the gear 98 is rotatably journalled in a plug or cap I02 having a circumferential groove I03 formed therein and which is received in a circular opening I04 provided in the top wall I8 of the housing I6. The groove I03 is designed for reception of the ends of a pair of set screws I05 which are threadedly received in the housing I6 and which serveto retain the plug or cap I02 in position within the opening I04. The driving gear 98 meshes with a driven gear I06 rotatably disposed in the housing 16 and the axis of which extends in a direction parallel to the axis of the gear 90. The gear I06 is keyed or otherwise secured to the medial region of a driven shaft I08 having a reduced end portion I09 rotatably journalled in an opening I I0 provided in the top wall I8. A groove I I I formed near the upper end of the reduced end I89 of the shaft I08 is adapted to receive a slotted retaining collar I I2 therein to assist in retaining the shaft I08 in position in the housing I6. A bearing washer H3 is disposed between the retaining collar H2 and the upper surface of the housing I6. An enlarged portion I I4 is formed on the shaft I08 and is rotatably journalled in an opening II6 provided in the bottom wall 80. An enlarged circular head I I8 is formed on the shaft I08 and occupies a position outside of the housing I6 beneath the bottom wall thereof. The head I I8 is provided with a clamping surface I20 which cooperates with a similar clamping surface I22 provided on the slotted head I24 of a clamping stud I26 threadedly received in a socket I28 provided in the enlarged portion I I4 of the shaft I08. The abrasive disc 94 is of circular design and is adapted to be received between the clamping surfaces I20 and I22 and is of sufiicient diameter and extent that when in position in the assembly I2 it underlies the bearing surface of the cupshaped member 86 in close proximity thereto.

The driving gear 98 is provided with a bore I30 extending therethrough and a cross pin I32 extends across the lower end of the bore I30 an is designed for register with a cut-away portion I34 provided in the lower end of the driving shaft I4 when the latter is received within the bore I30. The cross pin I32 and cut-away portion I34 of the shaft I4 provide an effective means for transmitting torque from the driving shaft I4 to the driving gear 98. A handle I36 is threadedly received in an opening I38 provided in the housing I6 and serves as a reaction member to prevent rotation of the housing I6 when the assembly I2 is in actual use and also serves as a manipulating member whereby the grinding apparatus may be readily transferred from one valve tappet to another in the valve chamber 28.

In the operation of the tappet grinding apparatus when it is desired to perform a complete tappet grinding operation on an automotive vehicle engine, the various valves I6, together with their retaining means including the spring 84, cup-washer 60 and retainer 62, are removed from the engine and a particular tappet, such as the tappet 54, is selected for processing. The drive shaft or spindle I4 is projected downwardly through the bore 22 provided in the valve guide 24. Meanwhile the assembly I2 is positioned in substantially the position illustrated in Figs. 1 and 3 with the underneath surface of the abrasive disc 94 resting on the upper worn end of the tappet 54. The shaft I4 is then introduced vertically into the bore I30 provided in the gear 98 and the cross pin I32 may be brought into register with the notch I34 by rotating either the drive shaft M or by swinging the housing 76 of the assembly. l2 about the axis of the tappet. A source of power, as for example the chuck C of a conventional electric hand drill (not shown), is applied to the upper end of the drive shaft 74 and with the operator holding the assembly it against rotation by means of the'handle I38, the drive shaft It is caused to rotate, thus turning the gears 98 and I06 and consequently rotating the abrasive disc 94; The underneath surface of the disc 94 is coated with a suitable abrasive material which frictionally engages the worn upper surface of the tappetts during the grinding operation. The disc 95 may be formed of horn fiber, Bakelite or a similar material having wear-resistant characteristics and may possess a certain degree of flexibilit whereby the underneath surface 90 of the cup-shaped member 85 may, by downward pressure on the housing :6 applied to the handle I35, force the abrasive surface of the disc 94 into engagement with the worn tappet surface. The abrasive element may, however, be formed as a rigid, unyielding member, in which case its inherent rigidity may be relied upon for the necessary abrasive pressure and the cup-shaped member 85 may then serve merely as a thrust member. After a few revolutions of the abrasive disc 94 the valve tappet 54 is completely processed and the upper surface thereof will be found to be smooth. Application of power to the drive shaft 14 may then be discontinued and the drive shaft I4 removed from the bore 22 without detaching the same from the chuck C. The drive shaft It may then be applied to a different guide and the operation repeated for processing the next selected tappet.

I believe that the construction and operation of my invention will be well understood from the foregoing description. It will be clear that I have provided a simple and inexpensive tappet grinder adapted for grinding valve tappets and the like while they are in assembled position in the engine, thereby reducing the cost of the grinding operation.

I claim:

1. In combination, an internal combustion engine block having a valve guide formed with a cylindrical bore, a valve-actuating element mounted on said block with a face spaced from one end of and in alignment with said bore, and a grinder comprising a casing disposed between said face and said one end of said bore, a drive member mounted in said casing and having an axial bore therein in alignment with the bore O said valve guide, a rigid drive spindle extending through the bore of said valve guide and projecting therefrom at one end for connection with drive means and projecting at the other end into the bore in said drive member, means betwee said spindle and said drive member non-rotatably connecting them while permitting detachment of said spindle merely by outward axial movement thereof, a driven member rotatably mounted in said casing and drive-connected with said drive member and having its axis parallel with and displaced laterally from the axis of said drive member, and a circular rotatable abrasive member carried by said driven member and disposed exteriorly of said casing, said abrasive member being of such diameter that its periphery is disposed in alignment with the axis of said drive member.

2. A device .of the class, and for the purpose described which comprises a casing, a drive member rotatably mounted in said casing'and having an axial bore therein, a drive spindle having. one end snugly projecting into said bore, means between said spindle and said drive member nonrotatably connecting-them :while permitting detachment of said spindle merelyby outward axial movement thereof, a drivenmember rotatably mounted in said casingand drive-connected with said drive'member and having its axis displaced laterally from the axis of saiddrive member, a

circular rotatable abrasive member carried by said driven member and disposed exteriorlypof said casing in a plane at right angles t'othe axis of said drive member and of such-diameter that its per iph'ery is disposed in' axial alignment with said drive member, and thrust means carried by said casing and disposed between the peripheral portion of said abrasive member and said casin in position to maintain the peripheral portion of said abrasive member at substantially right angles to the axis of said drive member when the former is engaged with a workpiece.

3. A device of the class and for the purpose described which comprises a casing, a drive member rotatably mounted in said casing and having an axial bore therein, a drive spindle having one end fitted in said bore, means between said spindle and said drive member non-rotatably connecting them while permitting detachment of said spindle merely by outward axial movement thereof, a driven member rotatably mounted in said casing and drive-connected with said drive member and having its axis displaced laterally from the axis ofsaid drive member, a rotatable, circular and flexible abrasive member carried by said driven member and disposed exteriorly of said casin with its periphery disposed in alignment with the axis of saiddrive member, and thrust means carried by said casing in alignment with the axis of said drive member inposition to engage the peripheral portion of said abrasive member to maintain said peripheral portion at substantially right angles to the axis of said drive member when said abrasive member is engaged with a workpiece.

4. A device of the class and for the purpose described which comprises a casing, a drive member rotatably mounted in said casing and having an axial bore therein, a rigid drive spindle having one end snugly projecting into said bore and its other end extending from the casing for connection with driving means, means between said spindle and said drive member non-rotatably connecting them while permitting detachment of said spindle merely by outward axial movement thereof, a driven member rotatably mounted in said casing and drive-connected with said drive member and having its axis parallel with and displaced laterally from the axis of said drive member, and a rotatable, circular and flexible abrasive disc carried by said driven member, said abrasive disc having an outer abrasive surface and an inner smooth surface and being of such diameter that its peripheral portion projects beyond the axis of said drive member, said casing having a pressure surface of substantial area disposed in alignment with and perpendicular to the axis of the drive member and lying substantially in the plane of the inner surface of the abrasive disc when the latter is in flat condition, said pressure surface being thereby positioned for engagement with the peripheral portion of the 7 disc and maintaining it in engagement with a workpiece.

5. A device of the class and for the purpose described which comprises a casing having a top, wall and a bottom wall, said top wall and bottom wall each having an opening with the openings in alignment with each other, a rigid cup-shaped member disposed in the opening in the bottom wall and having its bottom regions projecting outwardly from said casing and presenting a flat pressure surface, a gear having one end rotatably journalled in said cup-shaped member and the other end journalled in the opening in the top wall, said gear having an axial bore therein, a rigid drive spindle having one end snugly projecting into said bore, means between said spindle and said drive member non-rotatably connecting them while permitting detachment of said spindle merely by outward axial movement thereof, said bottom wall having a second opening, a driven shaft rotatably journalled in said casing and projecting downwardly through said second opening, a gear mounted on said driven shaft in mesh with said driving gear, a relatively thin flexible abrasive disc having a smooth upper surface and an abrasive bottom surface secured to said shaft outside the casing and being of such diameter as to underlie and engage said flat pressure surface, the peripheral region of said abrasive disc being disposed immediately under said pressure surface in position to be forced downwardly by said pressure surface against a workpiece under and in alignment with said pressure surface.

HENRY ROBERT BILLETER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 889,481 Murphy June 2, 1908 1,417,228 Blocker May 23, 1922 1,631,491 Klein June 7, 1927 1,800,341 Davies Apr. 14, 1931 1,950,264 Perazzoli Mar. 6, 1934 2,229,745 Kneisley Jan. 28, 1941 2,300,173 Platz Oct. 27, 1942 2,544,377 Cooke Mar. 6, 1951 

